Discovery of a novel Xanthone derivative P24 for anti-AD via targeting sTGFBR3.

Soluble transforming growth factor beta receptor 3 (sTGFBR3) antagonist is a new focus in the research and development of Alzheimer's disease (AD) drugs. Our previous studies have identified sTGFBR3 as a promising new target for AD, with few targeted antagonists identified. In this study, we performed structural modeling of sTGFBR3 using AlphaFold2, followed by high-throughput virtual screening and surface plasmon resonance assays. which collectively identified Xanthone as potential compounds for targeting sTGFBR3. After optimizing the sTGFBR3-Xanthone complex using molecular dynamics (MD) simulations, we prepared a series of novel Xanthone derivatives and evaluated their anti-inflammatory activity, toxicity, and structure-activity relationship in BV2 cell model induced by lipopolysaccharides (LPS) or APP/PS1/tau mouse brain extract (BE). Several derivatives with the most potent anti-inflammatory activity were tested for blood-brain barrier permeability and sTGFBR3 affinity. Derivative P24, selected for its superior properties, was further evaluated in vitro. The results indicated that P24 increased the activation of TGF-ß signaling and decreased the activation of IκBα/NF-κB signaling by targeting sTGFBR3, thereby regulating the inflammation-phagocytosis balance in microglia. Moreover, the low acute toxicity, long half-life, and low plasma clearance of P24 suggest that it can be sustained in vivo. This property may render P24 a more effective treatment modality for chronic diseases, particularly AD. The study demonstrates P24 serve as potential novel candidates for the treatment of AD via antagonizing sTGFBR3.

Notopterygium incisum roots extract (NRE) alleviates neuroinflammation pathology in Alzheimer's disease through TLR4-NF-κB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Notopterygium incisum Ting ex H. T. Chang, also called 'Qianghuo', is a distinct umbelliferae plant in China. The rhizomes and roots of Notopterygium incisum have long been used to treat headaches, colds, analgesia and rheumatoid arthritis. It is a main traditional Chinese medicine in Qianghuo Yufeng Decoction, which was used to treat diseases such as liver and kidney insufficiency, mental paralysis and dementia. AIM OF THIS STUDY: As the most common dementia, Alzheimer's disease (AD) has a complicated pathogenesis. So far, there is no effective drug to prevent its pathological process. Previous research has shown that Notopterygium incisum root extract (NRE) may inhibit the release of Aß and the activation of tau in mice with AD. However, the effect of NRE on the pathological process of neuroinflammation is still unclear. MATERIALS AND METHODS: We determined the pro-inflammatory cytokines levels in BV2 cells exposed to LPS/Aß42 after treated with NRE. APP/PS1 and LPS-induced C57BL/6 neuroinflammatory mice were given NRE for 8 weeks and 5 days respectively to detect the pathological changes of neuroinflammation. RESULTS: The findings showed that NRE had a notable inhibitory effect on the levels of TNF-α and IL-1ß in BV2 cells induced by LPS/Aß42. The results of in vivo experiments show that following NRE treatment, there was a notable decrease in the number of activated microglia in the hippocampus of APP/PS1 mice as indicated by immunofluorescence results. Sholl analysis showed that microglia branches increased in NRE group, indicating that M1 microglia activation was inhibited. In the mice model injected with LPS in the tail vein, PCR and Western Blot results confirmed the anti-inflammatory effect of NRE, Nissl staining showed the protective effect of NRE on neurons, and immunofluorescence results also indicated that the activation of M1 microglia was inhibited. CONCLUSION: These results suggest that long term oral administration of NRE may inhibit neuroinflammation in the progression of AD.

Nanoengineered therapeutic strategies targeting SNHG1 for mitigating microglial ischemia-reperfusion injury implications for hypoxic-ischemic encephalopathy.

The purpose of this work is to investigate the function of SNHG1, a long non-coding RNA implicated in disease progression, apoptosis, and proliferation, in order to solve the problem of hypoxic-ischemic encephalopathy (HIE) in newborn care. We investigated the impact of overexpressing SNHG1 on hypoxia-induced apoptosis and studied its expression in BV2 microglial cells under hypoxic circumstances. As a result of modifying YY1 expression, SNHG1's overexpression prevents apoptosis, as our data demonstrate that it is considerably downregulated under hypoxia. We demonstrate that SNHG1 might potentially reduce microglial ischemia-reperfusion damage by using sophisticated nanoengineering drug delivery technologies to target it. This provides encouraging information for the therapy of ischemic epilepsy.

Anti­epileptic mechanism of isopimaric acid from Platycladi cacumen based on network pharmacology, molecular docking and biological validation.

Platycladi cacumen (PC) is derived from the dry twigs and leaves of Platycladi orientalis (L.) Franco and exerts anti-epileptic effects. However, its mechanism of action remains unknown. The present study explored the potential anti-epileptic components and mechanisms of PC. The primary active components and targets of PC were analyzed using network pharmacology and a lipopolysaccharide (LPS)-induced murine microglial cell line (BV2) was used to confirm anti-epileptic effects by detecting reactive oxygen species (ROS), apoptosis, inflammatory markers, cell migration and signaling pathways. A total of 13 core active components showed druggable properties, of which deoxypicrop odophyllotoxin, hinokinin and isopimaric acid (IPA) were predicted to cross the blood-brain barrier. In total, 255 potential targets of these three compounds were predicted using SwissTargetPrediction and Similarity Ensemble Approach websites and 150 were associated with epilepsy. In vitro experiments confirmed that IPA significantly inhibited LPS-induced microglial oxidative stress and inflammation by decreasing the migration area, cellular ROS content, lactate dehydrogenase release and early phase of apoptosis. IPA also increased the mRNA expression of anti-oxidative enzymes (superoxide dismutase-1 and -2) and suppressed inflammatory cytokines (interleukin-1ß and tumor necrosis factor-α). Furthermore, IPA phosphorylated AKT and mTOR proteins. Taken together, the present findings suggested that IPA is a potential anti-epileptic compound derived from PC.

Deciphering the mechanism of cimifugin in mitigating LPS-induced neuroinflammation in BV-2 cells.

PURPOSE: Sepsis often triggers a systemic inflammatory response leading to multi-organ dysfunction, with complex and not fully understood pathogenesis. This study investigates the therapeutic effects of cimifugin on BV-2 cells under sepsis-induced stress conditions. METHODS: We utilized a BV-2 microglial cell model treated with lipopolysaccharide (LPS) to mimic sepsis. Assessments included cellular vitality, inflammatory cytokine quantification (6 interleukin [6IL]-1ß, interleukin 6 [IL-6], and tumor necrosis factor-α [TNF-α]) via enzyme-linked-immunosorbent serologic assay, and analysis of mRNA expression using real-time polymerase chain reaction. Oxidative stress and mitochondrial function were also evaluated to understand the cellular effects of cimifugin. RESULTS: Cimifugin significantly attenuated LPS-induced inflammatory responses, oxidative stress, and mitochondrial dysfunction. It enhanced cell viability and modulated the secretion and gene expression of inflammatory cytokines IL-1ß, IL-6, and TNF-α. Notably, cimifugin activated the deacetylase sirtuin 1-nuclear factor erythroid 2-related factor 2 pathway, contributing to its protective effects against mitochondrial damage. CONCLUSION: Cimifugin demonstrates the potential of being an effective treatment for sepsis--induced neuroinflammation, warranting further investigation.

Rhein inhibits M1 polarization of BV2 microglia through MAPK/IκB signalling pathway and reduces neurotoxicity caused by neuroinflammation.

BACKGROUND: Rhein is an anthraquinone compound with anti-inflammatory pharmacological activity. It has been found to play a neuroprotective role in neurological diseases, but the neuroprotective mechanism of rhein remains unclear. METHODS: SH-SY5Y cells serving as neuron-like cells and BV2 microglia were used. The toxicity of rhein on BV2 microglia and the viability of SH-SY5Y cells were measured by CCK-8 assay. The mRNA expression and secretion of pro-inflammatory cytokines were detected by qPCR and ELISA. Iba1, CD86 and pathway signalling protein in BV2 microglia were assessed by Western blot and immunofluorescence. Apoptosis of SH-SY5Y cells exposed to neuroinflammation was analysed through flow cytometry. RESULTS: Rhein inhibited MAPK/IκB signalling pathways. Further studies revealed that rhein inhibited the production of pro-inflammatory cytokines TNF-α, IL-6, IL-1ß and iNOS in BV2 cells and also inhibited the expression of M1 polarization markers Iba1 and CD86 in BV2 cells. Furthermore, rhein reduced the apoptotic rate and restored cell viability of SH-SY5Y cells exposed to neuroinflammation. CONCLUSIONS: Our study demonstrated that rhein inhibited microglia M1 polarization via MAPK/IκB signalling pathway and protected nerve cells through suppressing neuroinflammation.

A Pair of Epimers of Lignan Alleviate Neuroinflammatory Effects by Modulating iNOS/COX-2 and MAPK/NF-κB Signaling Pathways.

Neuroinflammation is a causative factor in neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease and amyotrophic lateral sclerosis. Previous studies have shown that Artemisia mongolica has anti-inflammatory properties. Aschantin (AM3) has been shown to have anti-inflammatory effects. However, the mechanism of AM3 and its epimer epi-aschantin (AM2) remains controversial. Therefore, the present study explored the mechanism of neuroinflammation by AM2 and AM3 and attempted to reveal the relationship between the structure of AM2 and AM3 and anti-neuroinflammatory activity. We isolated for the first time 12 lignans from A. mongolica that inhibited NO content at 10 µM in LPS-stimulated BV2 cells. Among them, epi-aschantin (AM2) and Aschantin (AM3) showed significant inhibition in NO screening. With further studies, we found that both AM2 and AM3 effectively inhibited the overproduction of NO, PGE2, IL-6, TNF-α and MCP-1, as well as the overexpression of COX-2 and iNOS. Mechanistic studies have shown AM2 and AM3 significantly inhibited the phosphorylation of ERK, JNK and P-38 in the MAPK signaling pathway and p-IκBα,p-p65 and blocked p65 entry into the nucleus. The results suggested that the pair of epimers (AM2 and AM3) can be used as potential therapeutic agents in the treatment of various brain disorders and that structural differences do not differ in anti-neuroinflammatory effects.

Four undescribed sesquiterpenes from Artemisia mongolica and their anti-inflammatory activity.

Four undescribed sesquiterpene compounds (1-4) and six known compounds (5-10) were isolated from A. mongolica. Furthermore, compound 5 was a new natural product previously synthesized. The LPS-stimulated BV2 cells were used as a model to evaluate the anti-inflammatory activity of the isolated compounds, among them, compounds 2, 3 and 4 showed significant inhibition of NO levels with IC50 values of 27.48, 27.39 and 24.96 µM, respectively.

Axially chiral dihydrophenanthrene dimers from Pholidota yunnanensis with anti-neuroinflammatory activities.

Axially chiral compounds are well known in medicinal chemistry of natural products, but their absolute configurations and bioactivities are rarely reported and studied. In this study, eleven undescribed axially chiral dihydrophenanthrene dimers, as well as twenty-five known dihydrophenanthrenes, were isolated from the entire plant of Pholidota yunnanensis. Their structures were elucidated by comprehensive spectroscopic analysis. A method for determining the absolute configurations of enantiomers was developed based on the rotational barriers and calculated ECD spectra. Additionally, the activities of all isolated compounds were assessed in LPS-induced BV-2 microglial cells. Most dihydrophenanthrenes exhibited significant NO inhibitory activities, and compound 7 showed the most potent inhibitory effect with an IC50 value of 1.5 µM, compared to the positive control minocycline. The immunofluorescence and western blot results revealed that compound 7 suppressed the expression of Iba-1, iNOS and COX-2 in LPS-stimulated BV-2 microglial cells.

A new cassane diterpenoid from the seed of Caesalpinia sappan.

In this study, a previously undescribed cassane diterpenoid, named caesalpinin JF (1), along with two known cassane diterpenoids caesanine C (2) and tomocinol B (3), was isolated from 95% EtOH extract of the seeds of Caesalpinia sappan Linn. Additionally, three known compounds including pulcherrin R (4), syringaresinol-4'-O-ß-D-glucopyranoside (5) and kaempferol (6) were also identified. The structures of the isolated compounds were elucidated by comprehensive 1D and 2D NMR spectroscopic analyses. Additionally, electronic circular dichroism (ECD) calculation was used to identify the absolute structure of compound 1. Among the isolated compounds, compound 1 displayed a potent anti-neuroinflammation with an IC50 value of 9.87 ± 1.71 µM.

The ROS/TXNIP/NLRP3 pathway mediates LPS-induced microglial inflammatory response.

BACKGROUND: Sepsis-associated encephalopathy (SAE) is a diffuse brain dysfunction activated by microglia. The potential pathological changes of SAE are complex, and the cellular pathophysiological characteristics remains unclear. This study aims to explore the ROS/TXNIP/NLRP3 pathway mediated lipopolysaccharide (LPS)-induced inflammatory response in microglia. METHODS: BV-2 cells were pre-incubated with 10 µM N-acetyl-L-cysteine (NAC) for 2 h, which were then reacted with 1 µg/mL LPS for 24 h. Western blot assay examined the protein levels of IBA1, CD68, TXNIP, NLRP3, ASC, and Cleaved Caspase-1 in BV-2 cells. The contents of inflammatory factor were detected by ELISA assay. The co-immunoprecipitation assay examined the interaction between TXNIP and NLRP3. RESULTS: LPS was confirmed to promote the positive expressions of IBA1 and CD68 in BV-2 cells. The further experiments indicated that LPS enhanced ROS production and NLRP3 inflammasome activation in BV-2 cells. Moreover, we also found that NAC partially reversed the facilitation of LPS on the levels of ROS, IL-1ß, IL-18, TXNIP, NLRP3, ASC, and Cleaved Caspase-1 in BV-2 cells. NAC treatment also notably alleviated the interaction between TXNIP and NLRP3 in BV-2 cells. CONCLUSION: ROS inhibition mediated NLRP3 signaling inactivation by decreasing TXNIP expression.

Characteristic terpenylated coumarins from Ferula ferulaeoides as potential inhibitors on overactivation of microglia.

A total of 37 characteristic terpenylated coumarins (1-25), including 17 undescribed compounds (1-5, 6a/6b, 7-10, 11a/11b-13a/13b), have been isolated from the root of Ferula ferulaeoides. Meanwhile, twelve pairs of enantiomers (6a/6b, 11a/11b-15a/15b, 17a/17b, 18a/18b, 20a/20b-22a/22b, and 25a/25b) were chirally purified. The structures of these new compounds were elucidated using HRESIMS, UV, NMR, and calculated 13C NMR with a custom DP4 + analysis. The absolute configurations of all the compounds were determined for the first time using electronic circular dichroism (ECD). Then, their inhibitory effects on nitric oxide (NO) production were evaluated with LPS-induced BV-2 microglia. Compared with the positive control minocycline (IC50 = 59.3 µM), ferulaferone B (2) exhibited stronger inhibitory potency with an IC50 value of 12.4 µM. The immunofluorescence investigation indicated that ferulaferone B (2) could inhibit Iba-1 expression in LPS-stimulated BV-2 microglia.

Exposure to urban particulate matter (UPM) impairs mitochondrial dynamics in BV2 cells, triggering a mitochondrial biogenesis response.

World Health Organisation data suggest that up to 99% of the global population are exposed to air pollutants above recommended levels. Impacts to health range from increased risk of stroke and cardiovascular disease to chronic respiratory conditions, and air pollution may contribute to over 7 million premature deaths a year. Additionally, mounting evidence suggests that in utero or early life exposure to particulate matter (PM) in ambient air pollution increases the risk of neurodevelopmental impairment with obvious lifelong consequences. Identifying brain-specific cellular targets of PM is vital for determining its long-term consequences. We previously established that microglial-like BV2 cells were particularly sensitive to urban (U)PM-induced damage including reactive oxygen species production, which was abrogated by a mitochondrially targeted antioxidant. Here we extend those studies to find that UPM treatment causes a rapid impairment of mitochondrial function and increased mitochondrial fragmentation. However, there is a subsequent restoration of mitochondrial and therefore cell health occurring concomitantly with upregulated measures of mitochondrial biogenesis and mitochondrial load. Our data highlight that protecting mitochondrial function may represent a valuable mechanism to offset the effects of UPM exposure in the neonatal brain. KEY POINTS: Air pollution represents a growing risk to long-term health especially in early life, and the CNS is emerging a target for airborne particulate matter (PM). We previously showed that microglial-like BV2 cells were vulnerable to urban (U)PM exposure, which impaired cell survival and promoted reactive oxygen species production. Here we find that, following UPM exposure, BV2 mitochondrial membrane potential is rapidly reduced, concomitant with decreased cellular bioenergetics and increased mitochondrial fission. However, markers of mitochondrial biogenesis and mitochondrial mass are subsequently induced, which may represent a cellular mitigation strategy. As mitochondria are more vulnerable in the developing brain, exposure to air pollution may represent a greater risk to lifelong health in this cohort; conversely, promoting mitochondrial integrity may offset these risks.

Chemical constituents from Notopterygium incisum and their anti-neuroinflammatory activity.

Phytochemical research on an extract of Notopterygium incisum yielded fifteen compounds (1-15), including four previously undescribed compounds (10-13). The structures of the unreported compounds were elucidated by spectroscopic and spectrometric data analysis such as 1D and 2D NMR, IR and HR-ESI-MS. Compounds 1-5 and 10-14 were isolated from N. incisum for the first time. 7S⁎,8R⁎-Phenethyl-(7-methoxy-8-isoeugenol)-ferulate (10), 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11), 7S⁎,8R⁎-benzyl-(7-methoxy-8-isoeugenol)-ferulate (12) and p-hydroxyphenethyl-(4-benzoy-3-methoxy)-cinnamate (13) are the undescribed ferulic acid derivatives. Additionly, the anti-neuroinflammatory effects of compounds were evaluated in lipopolysaccharide (LPS)-induced BV2 cells. The pharmacological results showed that 6ß,10ß-epoxy-4α-hydroxy-guaiane (6), teuclatriol (7) and 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11) inhibited the production and expression of nitric oxide (NO) in the LPS-induced BV2 cells in a concentration-dependent manner. Acorusnol (4), teucladiol (9), 7S⁎,8R⁎-benzyl-(7-methoxy-8-isoeugenol)-ferulate (12) and p-hydroxyphenethyl-(4-benzoy-3-methoxy)-cinnamate (13) only inhibited the release of NO at concentration of 20 µM. Moreover, 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11) reduced the level of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in LPS-stimulated BV2 cells. The results demonstrated 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11) could be a potential anti-neuroinflammatory agent and is worthy of further study.

Antioxidant aromatic compounds from Amomum villosum and target prediction of active ingredients.

The dried fruit of Amomum villosum is an important spice and medicinal plant that has received great attention in recent years due to its high content of bioactive components and its potential for food additives and drug development. However, the stems and leaves of A. villosum are usually disposed of as waste. Based on the study of the fruits of A. villosum, we also systematically studied its stems and leaves. Fourteen aromatic compounds (1-14) were isolated and identified from A. villosum, including five new compounds (1-5) and nine known compounds (6-14). Among them, compounds 2-5, 8-10, 12-13 were obtained from the fruits of A. villosum, and compounds 1, 6-7,11, 14 were isolated from the stems and leaves of A. villosum. Based on chemical evidence and spectral data analysis (UV, ECD, Optical rotation data, 1D and 2D-NMR, and HR-ESI-MS), the structures of new compounds were elucidated. Furthermore, all compounds were tested for their effects on the survival rate of BV-2 cells in the presence of hydrogen peroxide. Among them, compound 5 showed antioxidant effects. Through network pharmacology screening and the cell thermal shift assay (CETSA), the Phosphoglycerate Mutase 5 (PGAM5) protein was identified as the antioxidant target of compound 5. Molecular docking results showed that compound 5 maintains binding to PGAM5 by forming hydrogen bond interactions with Lys93 and Agr214. In summary, A. villosum had potential medicinal and food values due to the diverse bioactive components.

A Custom Panel for Profiling Microglia Gene Expression.

Despite being immune cells of the central nervous system (CNS), microglia contribute to CNS development, maturation, and homeostasis, and microglia dysfunction has been implicated in several neurological disorders. Recent advancements in single-cell studies have uncovered unique microglia-specific gene expression. However, there is a need for a simple yet elegant multiplexed approach to quantifying microglia gene expression. To address this, we have designed a NanoString nCounter technology-based murine microglia-specific custom codeset comprising 178 genes. We analyzed RNA extracted from ex vivo adult mouse microglia, primary mouse microglia, the BV2 microglia cell line, and mouse bone marrow monocytes using our custom panel. Our findings reveal a pattern where homeostatic genes exhibit heightened expression in adult microglia, followed by primary cells, and are absent in BV2 cells, while reactive markers are elevated in primary microglia and BV2 cells. Analysis of publicly available data sets for the genes present in the panel revealed that the panel could reliably reflect the changes in microglia gene expression in response to various factors. These findings highlight that the microglia panel used offers a swift and cost-effective means to assess microglial cells and can be used to study them in varying contexts, ranging from normal homeostasis to disease models.

Effects of environmentally relevant concentration of short-chain chlorinated paraffins on BV2 microglia activation and lipid metabolism, implicating altered neurogenesis.

Short-chain chlorinated paraffins (SCCPs), a class of persistent organic pollutants, have been found to cause diverse organ and systemic toxicity. However, little is known about their neurotoxic effects. In this study, we exposed BV2, a mouse microglia cell line, to environmentally relevant concentration of SCCPs (1 µg/L, 10 µg/L, 100 µg/L) for 24 h to investigate their impacts on the nervous system. Our observations revealed that SCCPs induced the activation of BV2 microglia, as indicated by altered morphology, stimulated cell proliferation, enhanced phagocytic and migratory capabilities. Analysis at the mRNA level confirmed the activation status, with the downregulation of TMEM119 and Tgfbr1, and upregulation of Iba1 and CD11b. The upregulated expression of genes such as cenpe, mki67, Axl, APOE and LPL also validated alterations in cell functions. Moreover, BV2 microglia presented an M2 alternative phenotype upon SCCPs exposure, substantiated by the reduction of NF-κB, TNF-α, IL-1ß, and the elevation of TGF-ß. Additionally, SCCPs caused lipid metabolic changes in BV2 microglia, characterized by the upregulations of long-chain fatty acids and acylcarnitines, reflecting an enhancement of ß-oxidation. This aligns with our findings of increased ATP production upon SCCPs exposure. Intriguingly, cell activation coincided with elevated levels of omega-3 polyunsaturated fatty acids. Furthermore, activated microglial medium remarkably altered the proliferation and differentiation of mouse neural stem cells. Collectively, exposure to environmentally relevant concentrations of SCCPs resulted in activation and lipid metabolic alterations in BV2 microglia, potentially impacting neurogenesis. These findings provide valuable insights for further research on the neurotoxic effect of SCCPs.

In vitro immunotoxicity effects of carbendazim were inhibited by n-acetylcysteine in microglial BV-2 cells.

Carbendazim (CBZ) is a benzimidazole fungicide widely used worldwide in industrial, agricultural, and veterinary practices. Although, CBZ was found in all brain tissues causing serious neurotoxicity, its impact on brain immune cells remain scarcely understood. Our study investigated the in vitro effects of CBZ on activated microglial BV-2 cells. Lipopolysaccharide (LPS)-stimulated BV-2 cells were exposed to increasing concentrations of CBZ and cytokine release was measured by ELISA, and Cytometric Bead Array (CBA) assays. Mitochondrial superoxide anion (O2·-) generation was evaluated by Dihydroethidium (DHE) and nitric oxide (NO) was assessed by Griess reagent. Lipid peroxidation was evaluated by measuring the malonaldehyde (MDA) levels. The transmembrane mitochondrial potential (ΔΨm) was detected by cytometry analysis with dihexyloxacarbocyanine iodide (DiOC6(3)) assay. CBZ concentration-dependently increased IL-1ß, IL-6, TNF-α and MCP-1 by LPS-activated BV-2 cells. CBZ significantly promoted oxidative stress by increasing NO, O2·- generation, and MDA levels. In contrast, CBZ significantly decreased ΔΨm. Pre-treatment of BV-2 cells with N-acetylcysteine (NAC) reversed all the above mentioned immunotoxic parameters, suggesting a potential protective role of NAC against CBZ-induced immunotoxicity via its antioxidant and anti-inflammatory effects on activated BV-2 cells. Therefore, microglial proinflammatory over-activation by CBZ may be a potential mechanism by which CBZ could induce neurotoxicity and neurodegenerative disorders.

Discovery of potential components characteristic by conjugated enone from the branches and leaves of Croton lauioides with anti-neuroinflammatory activity via regulating the NF-κB pathway.

In this study, the chemical composition and pharmacological activity of Croton lauioides were investigated for the first time. The bioactive and HPLC-UV guided isolation led to the discovery of twenty-three conjugated enone-type components (1-23), including nine previously unknown sesquiterpenoid derivatives (1-4, 9-10, 12-14). Notably, compounds 1 and 12 are epoxides containing an endoperoxide bridge (1) or a unique dioxaspiro core (12), respectively. Compounds 2-7 are non-benzenoid aromatics featuring a tropone function, while 9-11 possess a rare rearranged scaffold with tropone shift into benzene. Extensive characterization was performed using NMR spectra, HRESIMS data, and electronic circular dichroism (ECD) calculations. Furthermore, we evaluated the bioactivities of all isolated compounds against neuroinflammation in LPS-stimulated BV-2 microglial cells. Remarkably, most sesquiterpenoid derivatives exhibited significant NO inhibit activities, and compound 5 showed the most potent effect with an IC50 value of 0.14 ± 0.04 µM. Structure-activity relationship (SAR) analysis revealed that sesquiterpenoids modified with endocyclic enone conjugation may serve as a key pharmacophore for NO inhibition, particularly involving aromatic tropone moiety. The qPCR and Western blot results demonstrated that 5 exerted an inhibitory effect on the mRNA levels of iNOS, TNF-α and COX-2 in a time-dependent manner, as well as suppressed the protein expression of iNOS, TNF-α, COX-2. In mechanism, 5 could prevented activation of NF-κB pathway by suppressing phosphorylation of p65 and IκB-α. These findings revealed C. lauioides might be a promising resource for drug candidate development targeting neuroinflammation.

Manganese dioxide nanoparticles provoke inflammatory damage in BV2 microglial cells via increasing reactive oxygen species to activate the p38 MAPK pathway.

With the widespread use of manganese dioxide nanoparticles (nano MnO2), health hazards have also emerged. The inflammatory damage of brain tissues could result from nano MnO2, in which the underlying mechanism is still unclear. During this study, we aimed to investigate the role of ROS-mediated p38 MAPK pathway in nano MnO2-induced inflammatory response in BV2 microglial cells. The inflammatory injury model was established by treating BV2 cells with 2.5, 5.0, and 10.0 µg/mL nano MnO2 suspensions for 12 h. Then, the reactive oxygen species (ROS) scavenger (20 nM N-acetylcysteine, NAC) and the p38 MAPK pathway inhibitor (10 µM SB203580) were used to clarify the role of ROS and the p38 MAPK pathway in nano MnO2-induced inflammatory lesions in BV2 cells. The results indicated that nano MnO2 enhanced the expression of pro-inflammatory cytokines IL-1ß and TNF-α, elevated intracellular ROS levels and activated the p38 MAPK pathway in BV2 cells. Controlling intracellular ROS levels with NAC inhibited p38 MAPK pathway activation and attenuated the inflammatory response induced by nano MnO2. Furthermore, inhibition of the p38 MAPK pathway with SB203580 led to a decrease in the production of inflammatory factors (IL-1ß and TNF-α) in BV2 cells. In summary, nano MnO2 can induce inflammatory damage by increasing intracellular ROS levels and further activating the p38 MAPK pathway in BV2 microglial cells.